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    <title>log1p</title>
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    <center>Scilab Function</center>
    <div align="right">Last update : July 2001</div>
    <p>
      <b>log1p</b> -  computes with accuracy the natural logarithm of its argument added by one</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>y=log1p(x)  </tt>
      </dd>
    </dl>
    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>x</b>
        </tt>: real scalar, vector or matrix</li>
      <li>
        <tt>
          <b>y</b>
        </tt>: real scalar, vector or matrix</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
      <tt>
        <b>logp1(x)</b>
      </tt> is the "element-wise" log(1+x) function. <tt>
        <b>y(i,j)=log(1 + x(i,j))</b>
      </tt>.
    This function, defined for x &gt; -1, must be used if we want to compute log(1+x) with
    accuracy for |x| &lt;&lt; 1.</p>
    <h3>
      <font color="blue">Examples</font>
    </h3>
    <pre>

format("e",24)
log(1.001)
log1p(0.001)
log(1 + 1.e-7)
log1p(1.e-7)
log(1 + 1.e-20)
log1p(1.e-20)
format("v") //reset default format
   
  </pre>
    <h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="log.htm">
        <tt>
          <b>log</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
    <h3>
      <font color="blue">Author</font>
    </h3>
    <p>B.P.;   </p>
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